The Jackson Laboratory is a private non-profit research organization that was incorporated under the laws of Maine in 1929. The Jackson Laboratory has three program areas: research, training and resource. The Research Animal Facility (RAF) and the Laboratory Animal Health group serve these program areas by providing high quality comprehensive programs of animal husbandry, veterinary care and technical assistance. The renovation and equipment requested in this application are part of the long range plan for the RAF. This long range plan was initiated in 1986 and has been updated since then. Funds are requested to renovate space ("Radioisotope Area" 688 square feet in total) and to upgrade the ventilation system that supplies eleven mouse rooms, the "Radioisotope Area", and the Embryo Freezing Laboratory (13,061 square feet in total). The space proposed for renovation in this application is a suite of 1950's vintage rooms that are currently used as mouse rooms, radioisotope labeling laboratory and isotope waste storage area. The objective of the space renovation is to create and equip a diet preparation area, and to create three modern small mouse rooms that have clean and soiled supply corridors. The ventilation system proposed for renovation was upgraded in 1979, but cannot supply the required 10-15 air changes/hour, and does not have parallel fans. The objective of the ventilation renovation is to replace undersized ducts, install a parallel fan system that will provide 15-18 air changes per hour, and improve environmental controls. Parallel fans assure that partial ventilation can be provided when one fan must be shut down for maintenance or when mechanical failure occurs. Funds are also requested to purchase necessary equipment for the diet preparation area and to purchase equipment to isolate mice treated with isotopes or low level carcinogens or process their contaminated bedding.